I. Field of the Disclosure
The technology of the disclosure relates generally to a data bus and more particularly to a SOUNDWIRE™ data bus.
II. Background
Mobile electronic devices, such as mobile phones and computer tablets (i.e., “mobile terminals”), have become common in contemporary society for supporting various everyday uses. These electronic devices include a microphone and speakers. Typical microphones and speakers used in electronic devices have analog interfaces, requiring dedicated two (2) port wiring to connect each device. However, electronic devices may include multiple audio devices, such as multiple microphones and/or speakers. Thus, it may be desired to allow for a microprocessor or other control device in such electronic devices to be able to communicate audio data to multiple audio devices over a common communication bus. Further, it may also be desired to provide a defined communication protocol for transporting digital data relating to audio channels to different audio devices in an electronic device over a common communication bus.
In this regard, the MIPI® Alliance has announced SOUNDWIRE™ as a communication protocol for transporting data relating to audio channels to different audio devices associated with an electronic device. In SOUNDWIRE, one SOUNDWIRE master interface allows a master electronic device (“master” or “master device”), or monitor communicatively coupled thereto, to communicate over a common communication bus with up to eleven slave electronic devices (“slaves” or “slave devices”) coupled to SOUNDWIRE slave interfaces. As of this writing, the current version of SOUNDWIRE is revision 0.6-r02, which was made internally available on May 6, 2014 to MIPI Alliance members through the MIPI SharePoint file server.
SOUNDWIRE defines a procedure for slaves to connect to the SOUNDWIRE bus. The procedure involves an iterative process for slaves to receive bus specific addresses to avoid data collision. This process is sometimes referred to as enumeration because the master assigns to each slave a device number comprising a unique number between one (1) and eleven (11). Once all the slaves have been enumerated, normal operation of the SOUNDWIRE bus may occur. While effective at avoiding data collisions, the iterative process is relatively time consuming and must be repeated each time a device is powered on. Further, the iterative process generates duplicative commands which consume power. Such power consumption may be undesirable for battery powered mobile terminals.